Folding box



April 1953 w. J. BoscHE, JR 2,832,527

FOLDING BOX Filed April 2:, 195a EWMJW ,Vrramneys.

FOLDING BOX Walwin J. Bosche, Jr., Highland, Ill., assignor to Alton Box Board Company, Alton, Ill., a corporation of Delaware Application April 23, 1956, Serial No. 579,984

2 Claims. (Cl. 229--39) This invention relates to folding boxes, and more particularly to a folding box adapted to enclose a liquor bottle or other item of similar shape.

The invention contemplates the use of a self-locking bottom construction, which has the advantage of being conveniently set up by the user without adhesive or tape, but the side walls must be held in true rectangular relationship to one another. Accordingly, one of the objects of the invention is to provide a top closure for use in conjunction with such a self-locking bottom closure,

the top closure being of a character such that it can be quickly and conveniently closed to hold the side walls in rectangular relationship under forces otherwise tending to distort them. Among the several other objects of the invention may be noted the provision of a top closure which itself is self-locking; and the provision of a top closure which presents a neat symmetrical appearance and which is simple to make and set up.

Briefly, the invention contemplates that the box will have four side walls hingedly connected to one another, the side walls being relatively high in comparison to their width, and preferably being of the same width. A bottom closure flap is hinged to each of the four side walls, and these flaps are of a trapezoidal shape such that one side edge extends at right angles to the flap fold whereas the other side edge extends at an angle. The angle is such that the corresponding angled side edges of the several flaps generally meet in the center of the box, and in a square box, the angle would be forty-five degrees.

The top closure comprises a pair of flaps hinged to opposite side walls. A first one of these flaps, herein the lower flap, is formed with a tongue at its free end. A detent or slot then is formed in the side wall opposite from the one to which the lower flap is hinged, and this slot is positioned to receive the tongue or free end portion of the lower flap. The other top'closure flap has side flanges hinged along its side edges, and these flanges are adapted to lie against the inner surfaces of the corresponding side walls and to be held thereagainst by the side edges of the lower top-closure flap. Indeed, the side flanges should encounter a substantial frictional resistance in being forced between the lower top-closure flap and the side walls of the box, such frictional resistance tending to prevent inadvertent opening at the top. The tongue and slot action of the lower flap in combination with the upper flap thus provides a self-locking top closure.

Otherfeatures of the invention will be in part apparent and in part pointed out in the following detail de scription taken in connection with the accompanying drawings, in which:

Fig. 1 is a plan view of the blank from which the box is made;

Fig. 2 is a bottom plan view of a completed box illustrating the self-locking bottom;

Fig. 3 is an oblique view showing the top closure partially opened; and

2,832,527 Patented Apr. 29,1958

Fig. 4 is a vertical section through the top portion of the box but showing the top closure flaps in their closed positions.

Referring now to the drawings, the box is formed from a blank of semi-rigid material, such as corrugated paperboard. The blank is creased with corner folds 1, and bottom folds 3, which define side walls 5 and 7. The two ends 9 of the blank are brought together in a mannfacturers joint which might be sealed by means of an adhesive tape 11. A collapsible tube is thus formed, the tape 11 being applied by the box manufacturer. It will be noted the folds 3 are staggered relative to one another.

Bottom-closure flaps 13 are also formed to project from the lower folds 3. The four flaps 13 are of a length such as to meet one another in the center, and in a square box, their length would be half the width of the side walls. A first cut 15 is made along one side of each flap at right angles to fold 3 and a second cut 17 is made along the other side of each flap at an acute angle with respect to the fold 3. This second cut 17 should be at an angle such that the several side edges 7 of the flaps meet substantially in the center of the box. In the case of a square box, the angle of the cut at edge 17 would be forty-five degrees with respect to fold 3.

In setting up the bottom, the tube is opened to a rectangular shape and the bottom flaps are folded back within the tube. They are then released and guided as they spring back so that the side margin 15 of each flap overlies and interlocks with the adjacent margin 17 of an adjacent flap. The resulting bottom construction has a neat symmetrical appearance, which is desirable in the boxes of this type and is conveniently set up by the user. 0n the other hand, the side walls must be maintained in true rectangular relationship in order to insure that the bottom has adequate strength or resistance to opening. Also, it may be noted that the inherent resilience of the paperboard tends to cause the side walls to return to their collapsed condition, and if this distortion is permitted to go too far, the bottom closure will become undone. Consequently, it is desirable to provide for a condition at the top that can be quickly established to hold the side walls in their proper rectangular relationship. Since it is generally necessary to hold the side wall with one hand,

the top closure arrangement must be of a kind that can be quickly manipulated to a completed condition with the other hand.

This elfect is achieved by providing a pair of top closure flaps which are hinged to opposite side walls 5. The flap 19 is hinged to the side wall 5 along a line 2i and is cut so that its side edges 23 will be spaced slightly inwardly from the side walls 7. The free end portion of the flap 19 is then cut to provide a tongue 25, which is somewhat narrower than the full width of the box or flap. For example, the flap 19 may be cut with outwardly converging curved side edges 23. Also, the fold line 21 for flap 19 is olfset inwardly a slight distance from the top edges 27 of the adjacent side walls 7.

It may be noted that the first flap 19 (the lowermost top-closure flap) is of a length such as to extend completely across the box to the opposite side 5. A detentforming slot 28 is then cut in the opposite side Wall to receive the tongue 25. The tongue should be relatively rigid and of a width such as to interlock with the slot 28 when flap 19 is folded over along its hinge line 21. The slotted side wall may-yield outwardly a distance sutlicient to permit movement of the tongue into the slot, but the side walls are then locked in rectangular relationship. This feature is important because the user can thus quickly and conveniently secure the side walls so that the bottom will not become undone.

The top closure is then completed and more permanently secured by means of a second flap 29, which assess? 3 is adapted to overlie the flap 3.9. The second flap 29 is hinged to the slotted side wall 5 along a score 31, and this score is located immediately above the slot 28 or at a slight outward offset to the fold 2.1. Both the dimension of the slot and offset between folds 21 and 31 is determined by the thickness of the paperboard, which would normally be corrugated.

The upper flap 29 is also formed with side flanges 33, which are hinged along scores 35, the latter being offset inwardly a slight distance from cornerfolds ideally, the relationship of parts is one that develops a frictional gripping action as the side flanges 33 are forced between the edges 23 of the lower flap and the adjacent side walls 7. This frictional resistance tends to releasably hold the top flap 29. It may be noted that the frictional re sistance makes necessary the tongue-and-slot interlocl; for the underlying flap 19, because otherwise the fiap 19 might merely be pushed down into the box when flap 29 is folded over.

From the foregoing description, it is apparent that those skilled in the art Will understand the structure, function and mode of operation of the invention herein disclosed, and appreciate the advantages thereof. Although one embodiment has been disclosed in detail, it is to be understood that the invention is not limited thereto, but the drawings and description thereof are to be understood as being merely illustrative. It is realized that many modifications and variations will present themselves to those skilled in the art without departing from the spirit of this invention or the scope thereof as set forth in the appended claims.

Having thus described the invention, what is claimed and desired to be secured by Letters Patent is:

1. In a folding box having four hingedly connected side walls, the improvement that comprises a first top closure flap hingedly connected to one side Wall of the box, said first flap being of a length such as to extend to a second opposite side wall and having a semi-rigid tongue formed at its free end, a detent formed in said second side wall at the top thereof to interlock with said tongue and secure the first flap against inward displace ment, at second top-closure flap hinged to said second side 1 a line immediately above said detent, and l second llap being adapted to overlie the first flap and having side flanges which are engaged between the side edges of the first fiap and said other two side walls.

2. A box as set forth in claim 1, wherein said first topclosure flap is formed with side edges spaced inwardly an amount such as to develop a frictional engageinent with the side flanges of said second top-closure flan.

References Cited in the file of this patent UNITED STATES PATENTS 291,281 Blakely Jan. 1, 1884 340,904 Auchterlonie Apr. 27, 1886 930,882 Perkins Aug. 10, 1909 1,141,489 Richardson June 1, 1915 1,372,218 Davidson Mar. 22, 1921 1,446,250 Gibson Feb. 20, 1923 1,852,527 King Apr. 5, 1932 2,468,951 Barter May 3, 1949 2,682,988 Van Rosen July 6, 1954 FOREIGN PATENTS 253,665 Great Britain June 24, 1926 698,523 France Nov. 28, 1930 

